fix: user acquisition first user with last non direct source (#44)

Author: DianaMariia

models/50_intermediate/segment/int_segment__sessions_first_touch_point.sql

@@ -1,31 +1,59 @@
 {{ config(materialized="incremental", unique_key="canonical_segment_id") }}
 
 with
-    first_touch_anonymous as (
+    all_sessions as (
         select
             anonymous_id,
             canonical_segment_id_with_fallback as canonical_segment_id,
-            min(session_start_tstamp) as record_timestamp
+            referrer_source as src,
+            referrer_medium as med,
+            referrer_id as id,
+            session_start_tstamp as ts
         from {{ ref("int_segment__sessions") }}
+    ),
+
+    agg as (
+        select
+            canonical_segment_id,
+            anonymous_id,
+            array_agg(struct(src, med, id, ts) order by ts) as all_touches,
+            array_agg(
+                if(
+                    src in ('direct', 'session_continue'),
+                    null,
+                    struct(src, med, id, ts)
+                )
+                ignore nulls
+                order by ts
+            ) as non_direct_touches
+        from all_sessions
         group by 1, 2
     ),
 
     first_touch_canonical as (
         select
-            fa.anonymous_id,
-            fa.canonical_segment_id,
-            fa.record_timestamp,
-            s.referrer_id,
-            s.referrer_source,
-            s.referrer_medium
-        from first_touch_anonymous as fa
-        left join
-            {{ ref("int_segment__sessions") }} as s
-            on fa.anonymous_id = s.anonymous_id
-            and fa.record_timestamp = s.session_start_tstamp
+            canonical_segment_id,
+            anonymous_id,
+            coalesce(
+                (non_direct_touches[safe_offset(0)]).src,
+                (all_touches[safe_offset(0)]).src
+            ) as referrer_source,
+            coalesce(
+                (non_direct_touches[safe_offset(0)]).med,
+                (all_touches[safe_offset(0)]).med
+            ) as referrer_medium,
+            coalesce(
+                (non_direct_touches[safe_offset(0)]).id,
+                (all_touches[safe_offset(0)]).id
+            ) as referrer_id,
+            coalesce(
+                (non_direct_touches[safe_offset(0)]).ts,
+                (all_touches[safe_offset(0)]).ts
+            ) as record_timestamp
+        from agg
         qualify
             row_number() over (
-                partition by fa.canonical_segment_id order by fa.record_timestamp asc
+                partition by canonical_segment_id order by record_timestamp asc
             )
             = 1
     )